Spatial analysis of Fasciola hepatica prevalence in sheep flocks from Córdoba, Argentina using GWR and IDW models

Abstract

Fasciola hepatica is a zoonotic trematode with a widespread global distribution, impacting both livestock and humans. Despite its acknowledged effect on animal production, there is a lack of published data regarding its prevalence in sheep from the Cordoba ´ province, Argentina. This study aimed to evaluate the prevalence of F. hepatica in flocks across six departments in northwestern Cordoba ´ and to investigate the spatial and envi ronmental factors associated with infection. A total of 894 fecal samples from 27 sheep flocks were analyzed using sedimentation techniques. The overall prevalence was found to be 46 %, with the highest values observed in the Cruz del Eje and Pocho departments (74 %). Spatial analysis utilizing Inverse Distance Weighted (IDW) interpolation revealed a heterogeneous distribution, with a higher prevalence concentrated in the northern re gion. Geographically Weighted Regression (GWR) indicated that altitude was positively associated with preva lence, whereas a greater distance to water sources was negatively associated. These spatial patterns varied by subarea, underscoring the significance of local environmental conditions. Furthermore, 50 % of the farmers employed ineffective antiparasitic drugs, and only 5 % were aware of the zoonotic potential of the disease. This study constitutes the first spatially explicit report of ovine fasciolosis in Cordoba ´ and underscores the necessity for targeted control strategies that consider local risk factors.